package cn.zl.crawler;

import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.impl.conn.PoolingHttpClientConnectionManager;
import org.apache.http.util.EntityUtils;

import java.io.IOException;

/**
 * @author zhanglang
 * @Date 2020/3/16
 */
public class HttpClientPoolTest {
    public static void main(String[] args) {
        //创建连接池管理器
        PoolingHttpClientConnectionManager cm=new PoolingHttpClientConnectionManager();

        //设置连接数
        cm.setMaxTotal(100);

        //设置每个主机最大连接数
        cm.setDefaultMaxPerRoute(10);

        //使用连接池管理器发起请求
        doGet(cm);
        doGet(cm);
    }

    private static void doGet(PoolingHttpClientConnectionManager cm) {
        //不是每次创建新的HeepClient，而是从连接池中获取HttpClient对象
        CloseableHttpClient httpClient= HttpClients.custom().setConnectionManager(cm).build();

        HttpGet httpGet=new HttpGet("http://www.itcast.cn");

        CloseableHttpResponse response=null;

        try {
            response= httpClient.execute(httpGet);
            if (response.getStatusLine().getStatusCode()==200){
                String content= EntityUtils.toString(response.getEntity(),"utf8");

                System.out.println(content.length());
            }
        } catch (IOException e) {
            e.printStackTrace();
        }finally {
            if (response!=null){
                try {
                    response.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
                //不能关闭HttpClient，由连接池管理HttpClient
                //httpClient.close()
            }
        }
    }
}
